Test stand for solenoid switches

ABSTRACT

A test stand for conducting electrical tests on a solenoid switch, including a support platform containing a movable armature core for supporting the solenoid switch. A terminal head mounted on a support pedestal is positionable adjacent terminal posts on the solenoid switch and contains a plurality of electrical contacts which are connectable with electrical leads from a test console. A toggle clamp locks the terminal head in position adjacent the solenoid switch and the electrical contacts are spring biased to provide a positive mechanical contact between the terminal head contacts and the solenoid switch terminal posts.

United States Patent 1191 Helling TEST STAND FOR SOLENOID SWITCHES [21] Appl. No.: 524,252

[52] US. Cl 324/28 R; 324/158 F; 324/73 AT [51] Int. Cl. G01R 31/02 [58] Field of Search 324/28 R, 73 AT, 158 P, 324/158 F [56] References Cited UNITED STATES PATENTS 2,981,919 4/1961 Lamontetal ..324/28R 3,480,833 11/1969 Allen ..324/28R Nov. 18, 1975 Primary ExaminerAlfred E. Smith Assistant Eraminer-Michael J. Tokar ABSTRACT A test stand for conducting electrical tests on a solenoid switch, including a support platform containing a movable armature core for supporting the solenoid switch. A terminal head mounted on a support pedestal is positionable adjacent terminal posts on the solenoid switch and contains a plurality of electrical contacts which are connectable with electrical leads from a test console. A toggle clamp locks the terminal head in position adjacent the solenoid switch and the electrical contacts" are spring biased to provide a positive mechanical contact between the terminal head contacts and the solenoid switch terminal posts.

7 Claims, 4 Drawing Figures US. Patent Nov. 18, 1975 3,921,063

FIG. I

i/Fla. 2

TEST STAND FOR SOLENOID SWITCHES BACKGROUND OF THE INVENTION 1. Field of the Invention A test stand utilizing a movable armature core and a selectively positionable terminal head to lock a solenoid switch in place and actuate it while electrical tests are conducted.

2. Description of the Prior Art v Various types of magnetic or solenoid switches are utilized in combination with automobile starter motors for providing electrical current to the starter motor in response to theclosing of an ignition switch. Solenoid switches generally utilize an electrical coil which draws a movable armature core into the center of the coil when the coil is electrically energized. The movement of the armature core acts to close a mechanical switch which connects the automobile battery to the starter motor. When the coil is de-energized, the armature core is drawn out of the coil by spring biasing means, opening the switch between the battery and the starter motor.

Solenoid switches may malfunction due to several causes. The electrical contacts and leads which connect the solenoid coil to the ignition switch may become short circuited due to breakage of the electrical wiring or corrosion of the cable or connectors. The windings of the solenoid coil may become short circuited which would prevent the coil from drawing the armature core into it when activated. The armature core may fail to mechanically activate the switch connecting the battery to the starter motor. Even when the armature does properly close the switch connecting the battery to the starter motor, the contact surfaces within the mechanical switch may be short circuited. corroded or otherwise damaged, thereby preventing the flow of electrical current between the battery and the starter motor. In ceach of these instances of malfunction, a breakdown occurs in the flow of electrical energy to or through the solenoid switch. This breakdown in the conductivity can be detected by making various electrical measurements on the solenoid switch.

Presently available devices for conducting electrical checks on solenoid switches generally incorporate an electrical console which is connected to the terminal posts on the solenoid switch by means of electrical leads. After the electrical leads have been connected to the terminal posts of the solenoid switch, the mechanical switch within the solenoid is closed by using a probe or similar device to mechanically closethe switch. Such apparatus has been found to be inadequate in several regards. The use of simple alligator clips for connecting the test console to the solenoid switch terminal posts results in loose connections which may become disconnected or which may short out if contact is made between the various alligator clips or leads. Because several electrical leads are connected to the various terminal posts on the solenoid switch, it is possible to attach the leads to the wrong terminals resulting in invalid test results. Further, the use of a hand-operated device for closing the mechanical switch within the solenoid prevents the switch from being activated in the normal operating cycle of a solenoid switch. I

The difficulty in properly connecting a solenoid. switch to a test console is aggravated by the factthat the terminal posts of the solenoid switch generally have different diameters and protrude from the solenoid switch casing different lengths. This makes it difficult to provide means for adequately contacting all of the various length terminal posts using a single connector. In addition, the size of the solenoid switch for various trucks and automobiles varys slightly making it difficult to provide a test stand which suitably positions a wide range of solenoid types in a proper test position. Further. in testing solenoid switches, it is important that a positive electrical contact be maintained between the terminal posts of the solenoid switch and the electrical leads which extend to the test console.

SUMMARY The present invention provides a test stand by which electrical checks can be conducted on a solenoid switch of the type utilized on various vehicle starter motors. A support platform utilizing positioning pins which extend through the holes in the flange of the solenoid switch casing supports the solenoid switch during testing. An armature core slideably mounted on thesupport platform serves as the means for actuating the mechanical switch within the solenoid when the solenoid coil is energized and the armature core is drawn into the coil. Spring biasing means are utilized for urging the armature core into a withdrawn position when the coil is not energized.

A terminal head is positioned adjacent the terminal posts of the solenoid switch by means of a support pedestal attached to the support platform. A toggle clamp attached to the support pedestal allows the terminal head to be moved from a storage position to a fixed horizontal position adjacent the solenoid switch. Electrical leads from a test console connect to contact rods mounted in the terminal head. Each of the contact rods in the terminal head is part of a plunger mechanism which biases the contact rod in a forward position toward the solenoid switch. This allows each contact rod to abuttably contact an adjoining terminal post on the solenoid switch as the terminal head is locked into position, despite the differences in lengths of the terminal posts on the solenoid switch. The terminal head is movable laterally to allow the test stand to accommodate solenoid switches of various diameters. By providing fixed positions for the contact rods in the terminal head, the likelihood of mis-matching of the leads on the terminal posts is significantly reduced. and a positive electrical contact between all terminal posts and their respective test leads is achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the test stand in combination with a test console;

FIG. 2 is a side cross sectional view of the test stand generally along the line 22 of FIG. 1 with portions broken away and shown in section;

FlG. 3 is a fragmentary top plan view of the test stand taken generally along the line 3-3 in FIG. 2 showing the tenninal head in locked position adjacent a solenoid switch; and

FIG. 4 is a detailed top plan view of a solenoid switch showing the terminal post layout.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1-3, wherein like numerals refer to like structural elements, the present invention is a test stand 1 which can be utilized in combination with.

a test console 2 to run electrical checks on a solenoid switch 3. The test stand 1 incorporates a platform 16 which supports the solenoid switch adjacent to a support pedestal 17 which carries a test head 18. Various electrical cables (59-62) connect the test head 18 to the test console 2.

As is shown in FIGS. 2 and 4. a solenoid switch 3 will typically consist of a solenoid casing 4 having a terminal end 5 and a base end 6. The solenoid casing 4 serves as an electrical contact in the solenoid electrical circuit. A solenoid switch is typically attached to the starter motor of a vehicle by means of a base flange 32 which contains bolt holes 31. The solenoid switch 3 contains a hold-in winding coil 12a which surrounds a pull-in winding coil 12. Pull-in winding 12 surrounds a core opening 13. When the pull-in coil 12 is energized. electromotive forces a generated which tend to draw an armature into the core opening 13. The hold-in winding 12a then maintains the armature core in this position. As the armature moves into the core opening 13. it is intended to activate a mechanical switch 7 located adjacent the core opening 13. The mechanism (not shown) of mechanical switch 7 generally includes a contact disc (not shown) which is moved into contact between a battery terminal 8 and a starter terminal 9 (see FIG. 4) when mechanical switch 7 is closed by movement of the armature. This provides an electrical connection between the battery terminal 8 and the starter terminal 9 to provide electrical energy from the battery (not shown) to the starter motor (not shown).

In the embodiment shown in FIG. 2. the function served by the solenoid switch armature is duplicated by a facsimile armature core 22 which forms a part of the test stand I. The electrical coil 12 is energized when electrical current passes between a switch terminal post 10 and coil terminal post 11 which extend outwardly from the terminal end 5 of the solenoid switch (see FIG. 4). In operation. the switch terminal post 10 would be connected to the ignition switch (not shown) of the vehicle on which the solenoid is mounted so that coil 12 could be energized when the ignition switch was closed. It should be noted that the solenoid switch 3 which is shown on the drawings is representative of the type of devices which can be tested on test stand 1 and does not form part ofthe present invention.

Referring to FIGS. 1-2. test stand 1 provides a support platform 16 for supporting the solenoid switch 3. In the preferred embodiment. support platform 16 is comprised of a rectangular. electrically conductive aluminum plate 16a and a non-conductive panel 16/) to which is attached the test console 2 and support pedestal l7. Conductive plate 160 serves as a a conductor of current from the casing of solenoid switch 3 to test console 2 by means of cable 79 which is attached to plate 16a by means of fastening screw 80. Facsimile armature core 22 extends above support platform 16 and is intended to be inserted in the core opening 13 of the solenoid switch 3. Opposed positioning pins. each designated by the numeral 30, extend above the surface of support platform 16 and are intended to protrude into the bolt openings 31 of attachment flange 32 on solenoid switch 3. Positioning pins serve to index the solenoid switch 3 in proper alignment with armature core 22.

Referring to FIGS. 1 and 2, armature core 22 is mounted in support platform 16 by means of a mounting sleeve 20. Mounting sleeve 20 has a flange portion 14 which extends above support platform 16 and a restricted portion 14:: which extends into opening 19. Restricted portion 140 protrudes below the bottom surface of support platform 16 and contains threads 27 which receive a nut 21 and washer 21a for purposes of retaining the mounting sleeve 20 in place on support platform 16. Armature 22 is attached to a slender shaft 23 which extends through a bore 15 in mounting sleeve 20. Armature 22 is biased in a position wherein it abuts mounting sleeve 20 by means of a biasing spring 24. As is shown in FIG. 2, biasing spring 24 extends between mounting sleeve 20 and a spring retainer 25 which is attached to armature shaft 23 by means of a retention nut 26. In its normal extended position. armature biasing spring 24 extends between mounting sleeve 20 and spring retainer 25 to exert a biasing force on armature In order to conduct various electrical checks on the solenoid switch 3, it is necessary to apply a current across the various electrical elements of the solenoid switch and to measure the resulting response of the solenoid switch. Part of the function of the solenoid switch 3 is to close mechanical switch 7 by movement of armature 22 from its biased withdrawn position (FIG. 2) to a switch-closing position (not shown) wherein it contacts mechanical switch 7. This movement of armature 22 closes mechanical switch 7 to provide electrical connection between battery terminal 8 and starter terminal 9 (FIG. 4) to conduct current from a battery to the starter motor of the vehicle to which the solenoid switch is attached. After the hold-in coil of solenoid switch 3 has been denergized. an electromotive force is no longer generated and armature core 22 is returned to its biased position by means of spring 24.

Supp rt pedestal 17 is attached to support platform 16 for positioning the test head 18 adjacent the terminal end 5 of solenoid switch 3. As will be described in detail later. the test head 18 is movable from a storage position (shown in FIG. 1 and by dotted lines in FIG. 2) to a locked. generally horizontal position as is shown by the solid lines in FIG. 2. Support pedestal 17 consists of a base member 34 which is bolted to support platform 16 by means of bolts and nuts. each designated by the numeral and 35, respectively, which extend through base member 34. A vertical member 33 extends upwardly from base member 34 and attaches to a horizontal top member 36. In the preferred embodiment. vertical member 33 has a semi-circular cross section which is intended to provide additional clearance between the solenoid casing 4 and support pedestal 17.

Test head 18 includes a terminal head 37 which provides contact means between terminal posts 8-11 of solenoid switch 3 and electrical leads 59-62 from test console 2. In order to firmly hold solenoid switch 3 in place adjacent armature 22 with various contact means (to be described in detail later) in firm engagement with the terminal posts (841), test head 18 includes a toggle clamp 38 which secures terminal head 37 to support pedestal 17. Referring to FIGS. l-3, when terminal head 37 is moved into a horizontal position wherein it is adjacent the top of solenoid switch 3, it is desirable to lock the terminal head 37 in this position. When the solenoid switch is being removed from the test stand or positioned on the test stand, it is desirable that the terminal head 37 be moved to a storage position, indicated by the dotted lines in FIG. 2 and shown in FIG.

1. To provide this mobility to terminal head 37 while still allowing it to be locked into a horizontal position, toggle clamp 38 extends betwen terminal head 37 and support pedestal 17.

Referring to FIG. 2, toggle clamp 38 consists of a vertical member 29 connected to opposed flange members 28 which are bolted to the horizontal member 36 of support pedestal 17. Screws 42 are utilized for this purpose. Pivotally attached to vertical member 29 by pivot pin 64 is an extension arm 45. Extension arm 45 is also pivotally attached to clamp handle 40 at a pivot pin 44. By utilizing a pivot member 63 which extends between a pivot pin 41 on vertical member 29 and a pivot pin 44 on clamp handle 40, the extension arm 45 is moved into a locked, generally horizontal position when the clamp handle 40 is moved from a generally vertical position (shown by dotted lines in FIG. 2) to a below horizontal position (solid lines in FIG. 2). It should be noted that the toggle clamp 38 is a device well known in the art and the present description of the device will servce only to explain its functioning in properly positioning terminal head 37.

As is shown in FIG. 3, extension arm 45 is made up of two opposed extension arm members 45a which are spaced apart to form an extension arm opening 46. Terminal head 37 is slideably connected to extension arm 45 by means of a spindle 47 which extends through the extenion arm opening 46 and attaches to terminal head 37. Spindle 47 is held in place on extension arm 45 by means of opposed nuts, each designated by the numeral 47, and washers, each designated by the numeral 39. In the preferred embodiment, extension arm 45 extends outwardly from support pedestal 17 with its end positioned generally over the armature core 22. Spindle 47 can be moved laterally in extension arm opening 46 so that terminal head 37 can be properly positioned over the terminal posts 8-11 on solenoid switch 3. This allows the test stand l to be utilized on solenoid switches having slightly different spacing between its terminal posts.

It is the purpose of terminal head 37 to serve as a means for positioning various electrical leads (e.g. 59-62), extending from test console 2, in suitable position for maintaining an electrical contact between the leads and the terminal posts 8-11 on solenoid switch 3. To provide a reliable electrical contact between the electrical leads 59-62 and terminal posts 11, 8, and 9, respectively, the various electrical leads are attached to four contact plungers, each designated by the numeral 50, attached to terminal head 37. Since each of contact plungers 50 is of identical construction, a detailed description of their structure will be provided for only one of the contact plungers. As is shown in FIG. 2, contact plunger 50 consists of a contact rod 51 which slides in a plunger recess 56 in terminal head 37. Contact rod 51 has a connector end 53 which is attachable to a lead wire connector 58 (see FIG. 3) by means of opposed, spaced apart connector nuts 54. By turning connector nuts 54 on contact rod 51 with electrical connector 58 positioned between the connector nuts, the connector 58 is tightly held in place on contact rod 51. At the opposite end of contact rod 51 is a contact tip 52 having a diameter larger than that of contact rod 51. Contact tips 52 protrude beyond the surface of terminal head 37 to provide a contact point for abutting engagement with the top end of each of the solenoid switch terminal posts (e.g. 8-11). In the preferred embodiment, contact tip 52 is a disc constructed of aluminum or steel.

Since each of the terminal posts 8-11 on solenoid switch 3 is of a different length and has a different height above the support platform 16, it is necessary that each of contact rods 51 be movable in a vertical direction so that each will contact a terminal post when the terminal head 37 is in a single horizontal position. This flexibility is provided by means of plunger springs 55 which surround each of contact rods 51. Plunger springs 55 rest in a plunger recess 56 in terminal head 37. One end of each of springs 55 abuts the contact tip 52 and the opposed end abuts a shoulder ridge 57 in recess 56. In their normally extended position, springs 55 position contact tips 52 in an outwardly extended position from terminal head 37. As terminal head 37 is moved from its storage position to its locked horizontal position, various of the contact tips 52 will abut the top edge of the longerterminal posts. When this contact occurs, the contact rod 51 will be pushed upwardly through plunger recess 56 and the spring 55 will be compressed. As spring 55 is compressed, it maintains a forceful abutting contact between the contact tip 52 of contact rod 51 and the respective terminal post of solenoid switch 3. This assures a positive electrical contact between the two elements.

The horizontal position of terminal head 37 is selected so that the contact tip 52 of the lowest extending contact rod 51 will forcibly abut the top edge of the respective terminal posts of solenoid switch 3. In this manner, each of terminal posts 8-11 on solenoid switch 3 is in positive contact with its respective electrical lead (e.g. 59-62) which extends from test console 2. Because the contact rods 51 each has a fixed lateral position in terminal head 37 and because the solenoid switch 3 occupies a fixed position on positioning pins 30, it is nearly impossible for the personnel operating the test stand to mi s-match the test console leads (e.g. 59-62) with the terminal posts (e.g. 8-11) of solenoid switch 3.

Each of cables 59-62 is attachable to a solenoid terminal post 11, 8, 10,'and 9, respectively, and extends from terminal head 37 through housing 65 of test console 2. Electrical circuitry (not shown) within test console 2 connects the various leads to various measuring meters 62, 67 and 68 and a test light 69 on test console 2. By closing an ignition switch 70 on test console 2, pull-in coil 12 and hold-in coil are energized to draw armature 22 further into recess 13. This simulates turning on the vehicle ignition switch. After the ignition switch 70 on test console 2 has been closed, the light 69 will come on indicating that the test console is activated. Thus, to test a solenoid 3 in test stand 1, the solenoid is placed over armature 22 and terminal head 37 is moved to a locked position wherein contact tips 52 on contact rods 51 abut their respective terminal posts on the solenoid switch 3. The ignition switch 70 is then moved to a closed position to energize the coils l2 and 12a in solenoid switch 3. By moving double throw switch lever 72 to the upper position shown in FIG. 1 where it is engaged by contact elements 71, an electrical reading across the pull-in winding coil 12 is taken and displayed on the ammeter 62 on control console 2. When the switch element 72 is moved to the lower position where it is engaged by switch contacts 73, the amperage across the hold-in winding 12a is measured and displayed on ammeter 67 on test console 2. The

volt meter 68 on test console 2 measures the voltage across the mechanical switch 7 in solenoid switch 3. Thus, by properly setting the test switches 70-73 on test console, various electrical checks on the elements of solenoid switch 3 can be made.

In the event that a solenoid switch (not shown) is to be tested on which the terminal head 37 cannot be fitted, eg when the solenoid switch is very long, the terminal head 37 can be moved to its storage position and the solenoid switch can be positioned on support platform 16. A series of four auxiliary cabies 74-77, can then each be attached to the proper terminal posts of the solenoid switch being tested by means of alligator clips on the cables, each designated by the numeral 78. The test console 2 can then be operated in a similar manner to that described above for conducting a test on the solenoid switch. This latter arrangement of using auxiliary cables 74-77, corresponding to cables 59-62 respectively, allows the test stand 1 to be utilized on solenoids of various sizes. It should be noted that the present invention lies in the test stand 1 and the manner in which it can be combined with the test console 2 and not in the circuitry or operation of the test console itself.

What is claimed is:

l. A test stand for electrically functioning and testing a solenoid switch of the type having an electrical coil surrounding an armature recess, a mechanically actuated switch within the armature recess and a plurality of protruding terminal posts connectable to electrical leads, comprising:

a. a support platform engageable with the solenoid switch for holding it in a test position;

b. an armature core movably attached to said support platform, said armature core slidable within the armature recess from an inactive first position to an energized second position wherein it contacts the mechanically actuated switch;

0. biasing means attached to said armature core for urging it into said first position, said biasing means allowing the armature core to move to said second position when the electrical coil is energized;

d. a terminal head positionable adjacent the solenoid switch terminal posts for interconnecting the electrical leads with the terminal posts;

e. positioning means attached to said support member and to said terminal head for positioning the terminal head adjacent the solenoid switch;

f. movable contact elements attached to said terminal head, said contact elements each having a first end connectable to the electrical leads anda second end abuttable against the solenoid switch terminal posts; and

g. attachment means for movably attaching said contact elements to said terminal head with the contact elements abuttable against each of the solenoid switch terminal posts when the terminal head is positioned adjacent the solenoid switch.

2. The test stand of claim 1 wherein said positioning means comprise:

a. a support pedestal having a top portion and a base portion, said base portion being attached to said support platform;

b. a support member attached to said terminal head and movably attached to said support pedestal, said support member movable from a storage position to a test position wherein said terminal head is positioned adjacent the solenoid switch with said contact elements abutting the terminal posts; and

0. locking means for holding said support member in said test position to prevent movement of the sole noid switch.

3. The test stand of claim 2 wherein said contact element attachment means comprise:

a. said terminal head containing a plurality of recesses, each of said recesses slidably receiving one of said movable contact elements therein; and

b. a biasing spring attached to each of said contact elements, said biasing spring abuttable against said contact element and said terminal head to urge the second end of said contact element toward the terminal post of the solenoid switch thereby assuring a positive engagement between said contact element and the terminal post when said terminal head is positioned in its test position.

4. The test stand of claim 2 wherein said terminal head support member contains an elongated opening and a spindle member is attached to said terminal head, said spindle member positionable along said elongated opening to allow selective lateral positioning of said terminal head relative to said support pedestal.

5. The test stand of claim 1 wherein said support platform includes an electrically conductive surface engageable with the solenoid switch to provide an electrical connection between said support platform and the solenoid switch casing.

6. The test stand of claim 1 wherein said armature core biasing means comprise an elongated shaft attached to said armature core, said support platform containing an opening beneath said armature core through which said shaft extends, said shaft attached to a spring element which urges said armature core into said first position.

7. A test stand for electrically functioning and testing a solenoid switch of the type having an electrically conductive housing, an electrical coil surrounding an armature recess within the housing, a mechanically actuated switch within the armature recess and a plurality of protruding terminal posts connectable to electrical leads, comprising:

a. a support platform engageable with the solenoid switch for holding it in a test position, said support platform including an electrically conductive surface to provide an electrical connection between said support platform and the solenoid switch casmg;

. an armature core movably attached to said support platform, said armature core slidable within the armature recess from an inactive first position to an energized second position wherein it contacts the mechanically actuated switch;

c. a biasing spring attached to said armature core for urging it into said first position, said biasing spring allowing the armature core to move to said second position when the electrical coil is energized;

d. a support pedestal having a top portion and a base portion, said base portion being attached to said support platform;

e. a terminal head positionable adjacent the solenoid switch terminal posts for interconnecting the electrical leads with the terminal posts;

f. a support member attached to said terminal head and movably attached to said support pedestal, said support member movable from a storage position to a test position wherein said terminal head is positioned adjacent the solenoid switch with said Contact elements abutting the terminal posts;

g. locking means for holding said support member in said test position to prevent movement of the solenoid switch;

h. moveable contact rods attached to said terminal head, said contact rods each having a first end connectable to the electrical leads and a second end abuttable against the solenoid switch posts;

i. said terminal head containing a plurality of recesses, each of said recesses slidably receiving one of said contact rods therein; and

j. a biasing spring adjacent each of said recesses said biasing spring abuttable against said contact rod and said terminal head to urge the second end of said contact rod toward the terminal post of the solenoid switch thereby assuring a positive engagement between said contact rod and the terminal post when said terminal head is positioned in its 

1. A test stand for electrically functioning and testing a solenoid switch of the type having an electrical coil surrounding an armature recess, a mechanically actuated switch within the armature recess and a plurality of protruding terminal posts connectable to electrical leads, comprising: a. a support platform engageable with the solenoid switch for holding it in a test position; b. an armature core movably attached to said support platform, said armature core slidable within the armature recess from an inactive first position to an energized second position wherein it contacts the mechanically actuated switch; c. biasing means attached to said armature core for urging it into said first position, said biasing means allowing the aRmature core to move to said second position when the electrical coil is energized; d. a terminal head positionable adjacent the solenoid switch terminal posts for interconnecting the electrical leads with the terminal posts; e. positioning means attached to said support member and to said terminal head for positioning the terminal head adjacent the solenoid switch; f. movable contact elements attached to said terminal head, said contact elements each having a first end connectable to the electrical leads and a second end abuttable against the solenoid switch terminal posts; and g. attachment means for movably attaching said contact elements to said terminal head with the contact elements abuttable against each of the solenoid switch terminal posts when the terminal head is positioned adjacent the solenoid switch.
 2. The test stand of claim 1 wherein said positioning means comprise: a. a support pedestal having a top portion and a base portion, said base portion being attached to said support platform; b. a support member attached to said terminal head and movably attached to said support pedestal, said support member movable from a storage position to a test position wherein said terminal head is positioned adjacent the solenoid switch with said contact elements abutting the terminal posts; and c. locking means for holding said support member in said test position to prevent movement of the solenoid switch.
 3. The test stand of claim 2 wherein said contact element attachment means comprise: a. said terminal head containing a plurality of recesses, each of said recesses slidably receiving one of said movable contact elements therein; and b. a biasing spring attached to each of said contact elements, said biasing spring abuttable against said contact element and said terminal head to urge the second end of said contact element toward the terminal post of the solenoid switch thereby assuring a positive engagement between said contact element and the terminal post when said terminal head is positioned in its test position.
 4. The test stand of claim 2 wherein said terminal head support member contains an elongated opening and a spindle member is attached to said terminal head, said spindle member positionable along said elongated opening to allow selective lateral positioning of said terminal head relative to said support pedestal.
 5. The test stand of claim 1 wherein said support platform includes an electrically conductive surface engageable with the solenoid switch to provide an electrical connection between said support platform and the solenoid switch casing.
 6. The test stand of claim 1 wherein said armature core biasing means comprise an elongated shaft attached to said armature core, said support platform containing an opening beneath said armature core through which said shaft extends, said shaft attached to a spring element which urges said armature core into said first position.
 7. A test stand for electrically functioning and testing a solenoid switch of the type having an electrically conductive housing, an electrical coil surrounding an armature recess within the housing, a mechanically actuated switch within the armature recess and a plurality of protruding terminal posts connectable to electrical leads, comprising: a. a support platform engageable with the solenoid switch for holding it in a test position, said support platform including an electrically conductive surface to provide an electrical connection between said support platform and the solenoid switch casing; b. an armature core movably attached to said support platform, said armature core slidable within the armature recess from an inactive first position to an energized second position wherein it contacts the mechanically actuated switch; c. a biasing spring attached to said armature core for urging it into said first position, said biasing spring allowing the armature core to move to said second position when the electrical coil is energized; d. a support pedestal having a top portion and a base portion, said base portion being attached to said support platform; e. a terminal head positionable adjacent the solenoid switch terminal posts for interconnecting the electrical leads with the terminal posts; f. a support member attached to said terminal head and movably attached to said support pedestal, said support member movable from a storage position to a test position wherein said terminal head is positioned adjacent the solenoid switch with said contact elements abutting the terminal posts; g. locking means for holding said support member in said test position to prevent movement of the solenoid switch; h. moveable contact rods attached to said terminal head, said contact rods each having a first end connectable to the electrical leads and a second end abuttable against the solenoid switch posts; i. said terminal head containing a plurality of recesses, each of said recesses slidably receiving one of said contact rods therein; and j. a biasing spring adjacent each of said recesses, said biasing spring abuttable against said contact rod and said terminal head to urge the second end of said contact rod toward the terminal post of the solenoid switch thereby assuring a positive engagement between said contact rod and the terminal post when said terminal head is positioned in its test position. 